The present invention relates to devices for clearing large areas of noxious weeds and shrubs so that such areas may be returned to more effective grazing land. In particular, the present invention relates to a device having a (i) "V" -shaped scraper portion and a (ii) roller having knives mounted thereon for clearing and preparing an area for the introduction of grass seed.
A combination of factors have conspired over the past 40-50 years to render a large portion of the Western United States less than optimal range land. At the turn of the century, vast portions of the Western high desert were densely covered with highly nutritious range grasses, supporting large bison, and later domesticated cattle, populations. However, over grazing and artificial control of range fires have provided the opportunity for numerous unpalatable shrub species to invade and out-compete the native grasses. Historically, naturally occurring fires burned large areas and acted as a check on the growth of non-climax shrubs, such as sagebrush, rabbit brush, snake weed, juniper and saplings. Modern fire control techniques have essentially eliminated fire as a weed-control mechanism, and when combined with grazing intended to maximize the carrying capacity of dry land range, have provided a ripe environment for proliferation of noxious weeds and shrubs.
After the invasion of such weeds (hereinafter, the full range of noxious invaders will be shortened to "sagebrush", although it is to be understood that such word includes the others noted above), little has been done to reclaim the range land back to its original condition. Numerous methods for sagebrush control have been proposed, none with any degree of widespread success. For example, devices are available to burn off individual sagebrush plants without starting range fires. Likewise, chemicals have been attempted but with little or no success--either they were not effective to kill mature plants, or they were too expensive, left a toxic residue, or killed virtually everything and permitted sagebrush, not grasses, to immediately invade. Mechanical devices have been attempted, such as so-called "brush-hogs" and disking/plowing. However, the latter was incapable of destroying a mature plant, while the former required too much power, such as a tracked tractor or a 6-8 wheel drive vehicle, with the consequent increased cost of operation.
The prior art methods of control, if marginally effective at all, were limited to treatment of approximately 5 acres per day, not great enough treatment to be economically viable. It is believed that it will be necessary to treat at least 40, and preferably 80, acres per day, with lower cost 2-wheel drive tractors, in order to make it feasible to clear large quantities of sagebrush-infested areas.
Accordingly, it is an object of the present invention to provide an apparatus which can be towed by a conventional 2-wheel drive tractor over an area of range land infested with sagebrush, thereby clearing the sagebrush for the planting of grass seed. It is a further object of the present invention to provide a method for the clearing of sagebrush-infested range land and the simultaneous planting of grass seed, thereby returning the range land to its more normal grassland state.